CN110286310B

CN110286310B - Testing device based on semiconductor wafer surface

Info

Publication number: CN110286310B
Application number: CN201910694893.7A
Authority: CN
Inventors: 肖凌; 陈秉克; 吴会旺; 赵丽霞
Original assignee: HEBEI POSHING ELECTRONICS TECHNOLOGY CO LTD
Current assignee: HEBEI POSHING ELECTRONICS TECHNOLOGY CO LTD
Priority date: 2019-07-30
Filing date: 2019-07-30
Publication date: 2021-04-27
Anticipated expiration: 2039-07-30
Also published as: CN110286310A

Abstract

The invention provides a testing device based on the surface of a semiconductor wafer, which belongs to the technical field of semiconductors and comprises a testing platform, a bracket, a probe assembly, a driving part and a flexible connecting piece. According to the semiconductor wafer surface-based testing device provided by the invention, the probe assembly is hung on the support through the flexible connecting piece, when the semiconductor wafer is tested, the driving part drives the probe assembly to approach the semiconductor wafer fixed on the test board along the vertical direction through the flexible connecting piece, and because the probe assembly is flexibly connected with the flexible connecting piece, the probe assembly can rotate around the contact end of the probe assembly and the semiconductor wafer by means of self gravity until the lower surface of the probe assembly is completely attached to the upper surface of the semiconductor wafer, so that the automatic adjustment of the probe assembly is realized, the testing area of the probe assembly on the semiconductor wafer is ensured, and the testing efficiency and the testing precision are improved.

Description

Testing device based on semiconductor wafer surface

Technical Field

The invention belongs to the technical field of semiconductors, and particularly relates to a testing device based on the surface of a semiconductor wafer.

Background

The existing testing device in the market places a semiconductor wafer on a testing platform, places a point to be tested of the semiconductor wafer below a probe in a mode of left-right movement and horizontal rotation of the testing platform in the testing process, a mechanical arm is fixedly connected with the probe through a connecting piece, the mechanical arm controls the probe to fall down to enable the probe to be in contact with the surface of the semiconductor wafer, mercury contained in the probe is connected with the surface of the semiconductor wafer to complete a circuit loop, and CV/IV testing (namely, measuring the carrier concentration of a semiconductor material) is achieved. The contact area of the probe and the semiconductor wafer is an important parameter in the test process, the contact surfaces of the probe and the semiconductor wafer are both flat, and the ideal state is that the contact surfaces of the probe and the semiconductor wafer are kept parallel. Because the testboard is wearing and tearing for a long time and dismouting and level and rotary motion in-process, can't guarantee that testboard and probe keep on same horizontal plane, lead to the lower surface of probe and the upper surface of semiconductor wafer to have the contained angle and the contained angle between different test points is different, consequently need operating personnel to adjust the probe to suitable angle, make probe and semiconductor wafer keep parallel, seriously influence efficiency of software testing, because there is the error in artifical debugging, lead to the unable assurance of test accuracy.

Disclosure of Invention

The invention aims to provide a testing device based on the surface of a semiconductor wafer, aiming at solving the problems of low testing efficiency and low testing precision of the conventional testing device.

In order to achieve the purpose, the invention adopts the technical scheme that: there is provided a semiconductor wafer surface based test apparatus comprising:

a test table for placing a semiconductor wafer;

the bracket is arranged on one side of the test board;

a probe assembly for contacting an upper surface of a semiconductor wafer;

the driving part is arranged on the bracket and used for driving the probe assembly to move along the vertical direction; and

the flexible connecting piece is used for connecting the probe assembly and the driving part;

the probe assembly moves downwards by virtue of the flexible connecting piece to be in contact with the semiconductor wafer, and rotates around the contact end of the probe assembly and the semiconductor wafer by virtue of self gravity until the lower surface of the probe assembly is completely attached to the upper surface of the semiconductor wafer.

Further, the flexible connecting piece is a string.

Furthermore, the bottom of flexible connectors is equipped with the connecting portion that the probe subassembly is connected, the quantity of connecting portion is three, follows the focus evenly distributed of probe subassembly.

Further, the probe assembly includes:

a probe base;

the mercury probe is fixedly arranged on the probe base; and

and the supporting rod is arranged on the probe base and is used for supporting the probe base.

Further, the top of the probe base is provided with a groove, and a pin shaft for fixedly connecting the flexible connecting piece is arranged inside the groove.

Furthermore, the number of the support rods is two, and the support rods are symmetrically arranged on two sides of the mercury probe head.

Further, the supporting rod is connected with the probe base through threads and has a degree of freedom of rotation around the axis of the supporting rod.

Further, the driving part includes:

the rotating shaft is rotatably arranged on the bracket;

the worm wheel is fixedly arranged on the rotating shaft, and one end of the worm wheel is provided with a shaft sleeve for winding the flexible connecting piece; and

and the worm is rotatably arranged on the bracket and is in transmission fit with the worm wheel.

Furthermore, a guide wheel is arranged on the support and located between the driving part and the probe assembly, a guide groove is formed in the periphery of the guide wheel, and the flexible connecting piece is pressed on the side wall of the guide groove.

Further, the driving part further includes:

the rotating disc is fixed at one end of the worm and rotates coaxially with the worm; and

and the handle is hinged on the end surface of the rotating disc.

The testing device based on the surface of the semiconductor wafer has the advantages that: compared with the prior art, the testing device based on the surface of the semiconductor wafer adopts the flexible connecting piece to hoist the probe assembly on the support, when the semiconductor wafer is tested, the driving part drives the probe assembly to approach the semiconductor wafer fixed on the test board along the vertical direction through the flexible connecting piece, and the probe assembly can rotate around the contact end of the probe assembly and the semiconductor wafer by the self gravity until the lower surface of the probe assembly is completely attached to the upper surface of the semiconductor wafer due to the flexible connection between the probe assembly and the flexible connecting piece, so that the automatic adjustment of the probe assembly is realized, the testing area of the probe assembly on the semiconductor wafer is ensured, and the testing efficiency and the testing precision are improved.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed for the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a testing apparatus based on a semiconductor wafer surface according to embodiment 1 of the present invention;

fig. 2 is a schematic structural diagram of a probe assembly provided in embodiment 1 of the present invention;

FIG. 3 is a schematic structural view of a probe assembly provided in embodiment 2 of the present invention;

FIG. 4 is a schematic cross-sectional view of a probe assembly according to embodiment 2 of the present invention;

fig. 5 is a schematic perspective view of a driving portion provided in embodiment 1 of the present invention;

fig. 6 is a schematic perspective view of a worm wheel according to embodiment 1 of the present invention;

fig. 7 is a schematic perspective view of a guide wheel provided in embodiment 1 of the present invention.

In the figure: 1. a test bench; 2. a semiconductor wafer; 3. a support; 301. a guide wheel; 302. a guide groove; 4. a probe assembly; 401. a probe base; 402. a mercury probe tip; 403. a support bar; 404. a groove; 405. a pin shaft; 406. a grip portion; 407. a spring; 408. a rubber suction cup; 409. a first limiting flange; 410. a second limiting flange; 5. a drive section; 501. a rotating shaft; 502. a worm gear; 503. a worm; 504. a shaft sleeve; 505. rotating the disc; 506. a handle; 6. a flexible connector; 601. a connecting portion.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention more clearly apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Referring to fig. 1, a testing apparatus for testing a semiconductor wafer according to the present invention will now be described. The testing device based on the surface of the semiconductor wafer comprises a testing platform 1, a bracket 3, a probe assembly 4, a driving part 5 and a flexible connecting piece 6. The test bench 1 is used for placing a semiconductor wafer 2; the bracket 3 is arranged at one side of the test bench 1; the probe assembly 4 is for contacting the upper surface of the semiconductor wafer 2; the driving part 5 is arranged on the bracket 3 and is used for driving the probe assembly 4 to move along the vertical direction; the flexible connector 6 is used to connect the probe assembly 4 and the drive section 5. The driving part 5 drives the probe assembly 4 to move downwards by virtue of the flexible connecting piece 6 to be in contact with the semiconductor wafer 2, and rotates around the contact end of the probe assembly 4 and the semiconductor wafer 2 by virtue of the self gravity of the probe assembly 4 until the lower surface of the probe assembly 4 is completely attached to the upper surface of the semiconductor wafer 2.

Compared with the prior art, the testing device based on the surface of the semiconductor wafer provided by the invention has the advantages that the probe assembly 4 is hung on the support 3 by the flexible connecting piece 6, when the semiconductor wafer 2 is tested, the driving part 5 drives the probe assembly 4 to approach the semiconductor wafer 2 fixed on the test board 1 along the vertical direction through the flexible connecting piece 6, the probe assembly 4 is flexibly connected with the flexible connecting piece 6, the probe assembly 4 can rotate around the contact end of the probe assembly 4 and the semiconductor wafer 2 by means of the gravity of the probe assembly 4 until the lower surface of the probe assembly 4 is completely attached to the upper surface of the semiconductor wafer 2, the automatic adjustment of the probe assembly 4 is realized, the test area of the probe assembly 4 on the semiconductor wafer 2 is ensured, and the test efficiency and the test precision are improved.

Referring to fig. 1, a flexible connecting member 6 is a string, which is an embodiment of the testing apparatus based on the surface of the semiconductor wafer according to the present invention. When probe subassembly 4 moves along vertical direction, because the cotton rope can not stretch out and draw back, can prevent effectively that probe subassembly 4 from following vertical direction's vibration, be favorable to finding the test point accurately, improve the degree of accuracy of test. The cord has the advantage of cost and is easy to obtain, and the production cost can be effectively reduced. When the cable hoists the probe assembly 4, the cable is in a straightening state; when the probe assembly 4 and the semiconductor wafer 2 are in the processes from the initial contact to the complete joint, the wire rope provides tension for the probe assembly 4 all the time, so that the probe assembly 4 is more stable in the rotating process. The diameter of the wire rope is below 1mm, and when the wire rope is in a loose state, the stability of the probe assembly 4 cannot be influenced due to the light weight of the wire rope. The cotton rope can also adopt glass fiber (glass fiber), and the glass fiber has good insulating nature and rigidity, and the surface of glass fiber is smooth simultaneously, and self can not produce the pollutant, and easy clearance. The diameter of the glass fiber is 5-10 μm, which can not only ensure the mechanical strength, but also reduce the occupied space and the self weight.

Referring to fig. 1, as a specific implementation manner of the embodiment of the present invention, the bottom end of the flexible connecting member 6 is provided with three connecting portions 601 connected to the probe assembly 4, and the connecting portions 601 are uniformly distributed along the center of gravity of the probe assembly 4. The three connecting portions 601 provide three evenly distributed supporting points for the probe assembly 4, and further improve the stability of the probe assembly 4.

Referring to fig. 1 and 2, as a specific implementation of the embodiment of the present invention, the probe assembly 4 includes: a probe base 401, a mercury probe tip 402 and a support bar 403. The mercury probe 402 is fixedly arranged on the probe base 401; a support bar 403 is provided on the probe base 401 for supporting the probe base 401. The mercury probe 402 is fixed at the bottom of the probe base 401 through threads or bonding, and the probe base 401 is correspondingly provided with a mounting hole of the mercury probe 402. The mercury probe 402 is a cylinder, and the lower bottom surface thereof is a plane for contacting with the upper surface of the semiconductor wafer 2, so as to test the semiconductor wafer 2. The semiconductor wafer 2 is inclined below 0.5 ° from the horizontal plane due to mechanical errors of the test stand 1, and the inclination of the semiconductor wafer 2 is insufficient to allow the mercury probe tip 402 to slide or tip along the upper surface of the semiconductor wafer 2. The support rods 403 are used as auxiliary supports to provide sufficient support for the mercury probe head 402, so that the mercury probe head 402 and the semiconductor wafer 2 are more stable, and the test result is more accurate. The support rods 403 are made of teflon, which does not adhere any substance and prevents impurities or contaminants from contaminating the semiconductor wafer 2 by adsorbing on the support rods 403.

Referring to fig. 2, as a specific implementation manner of the embodiment of the present invention, a groove 404 is formed at the top of a probe base 401, and a pin 405 for fixedly connecting a flexible connecting member 6 is disposed inside the groove 404. One end of the flexible connecting piece 6 is tied on the pin 405 for fixing, so that the flexible connecting piece 6 is more convenient to install. The top of the probe base 401 can also be provided with a lifting ring, the lifting ring is fixedly connected with the probe base 401 through threads, and one end of the flexible connecting piece 6 is fixed on the lifting ring.

As a specific implementation manner of the embodiment of the present invention, please refer to fig. 2, the number of the support rods 403 is two, and the two support rods are symmetrically disposed at two sides of the mercury probe head 402. The two support rods 403 and the mercury probe head 402 form a three-point support, so that the structure is more stable.

Referring to fig. 2, a support rod 403 is connected to a probe base 401 through a screw thread and has a degree of freedom to rotate around its axis. Before the mercury probe tip 402 contacts the semiconductor wafer 2, the support rods 403 are rotated to a retracted state (i.e., the bottom surfaces of the support rods 403 are higher than the bottom surface of the mercury probe tip 402) by the screw connection with the tip base 401; after the mercury probe 402 is completely contacted with the semiconductor wafer 2, the support rod 403 is rotated and lowered until the support rod 403 is just contacted with the upper surface of the semiconductor wafer 2, so as to realize the auxiliary supporting function of the support rod 403. The bottom end of the support bar 403 is an arc surface, and the support bar 403 is in point contact with the upper surface of the semiconductor wafer 2. The top end of the support rod 403 is provided with a holding part 406, and the holding part 406 is cross-shaped, so that an operator can rotate the support rod 403 conveniently.

Referring to fig. 3 and 4, as a specific implementation manner of the embodiment of the present invention, a support rod 403 is installed on a probe base 401 in a sliding manner along a vertical direction, and the probe base 401 is correspondingly provided with a sliding groove matched with the support rod 403. The periphery of the support rod 403 is sleeved with a spring 407, and the bottom end of the support rod 403 is provided with a rubber suction cup 408. The support bar 403 is provided with a first limiting flange 409 and a second limiting flange 410. The first limiting flange 409 is positioned above the probe base 401, one end of the spring 407 abuts against the first limiting flange 409, and the other end abuts against the top surface of the probe base 401; the second limiting flange 410 is located below the probe base 401, and the first limiting flange 409 is matched with the second limiting flange 410 to limit the supporting rod 403 on the probe base 401. When the mercury probe 402 is completely contacted with the semiconductor wafer 2, the support rod 403 is pressed downwards, the spring 407 is compressed, the rubber suction cup 408 moves downwards along with the support rod 403 and is adsorbed on the surface of the semiconductor wafer 2, so that the whole probe assembly 4 is fixed on the semiconductor wafer 2; after the test is completed, the rubber suction cup 408 is separated from the semiconductor wafer 2, and the spring 407 is naturally released to drive the supporting rod 403 to move upwards to the initial state, so that the supporting rod 403 is automatically retracted, and the labor intensity is reduced.

As a specific implementation manner of the embodiment of the present invention, referring to fig. 1, 5 and 6, the driving portion 5 includes: a rotating shaft 501, a worm wheel 502 and a worm 503. The rotating shaft 501 is rotatably arranged on the bracket 3; a worm gear 502 is fixedly arranged on the rotating shaft 501, and one end of the worm gear 502 is provided with a shaft sleeve 504 for winding the flexible connecting piece 6; the worm 503 is rotatably disposed on the bracket 3 and is in driving engagement with the worm wheel 502. The shaft sleeve 504 and the worm wheel 502 are integrally formed, so that the number of parts is reduced, and the assembly efficiency is improved. The transmission mode of the worm wheel 502 and the worm 503 is adopted, the structure is simple, the occupied space is small, the transmission is more stable and reliable, meanwhile, the structure can realize self-locking, and the safety of the testing device is ensured. The driving section 5 may be a dc or ac motor.

As a specific implementation manner of the embodiment of the present invention, referring to fig. 1, fig. 5 and fig. 7, a guide wheel 301 is disposed on the bracket 3, the guide wheel 301 is located between the driving portion 5 and the probe assembly 4, a guide groove 302 is disposed on an outer periphery of the guide wheel 301, and the flexible connecting member 6 is pressed against a side wall of the guide groove 302. The guide wheel 301 can rotate around its own axis and is parallel to the axis of the worm wheel 502. The guide groove 302 is a V-shaped groove and can adapt to flexible connectors 6 of different sizes. During the winding process of the flexible connecting piece 6 on the shaft sleeve 504, the motion track of the flexible connecting piece can be changed; after the flexible connecting piece 6 is restrained and limited by the guide groove 302, the movement state is more stable, and the shaking of the probe assembly 4 is effectively prevented.

As a specific implementation manner of the embodiment of the present invention, referring to fig. 1, the driving portion 5 further includes: a turn disc 505 and a handle 506. A rotating disc 505 is fixed at one end of the worm 503 and rotates coaxially with the worm 503; a handle 506 is hinged to the end face of the turn disc 505. The end surface of the rotating disc 505 is perpendicular to the axial direction of the worm 503. The handle 506 is located at one end of the end face far away from the worm 503, which facilitates the operation of the operator and saves the labor intensity of the operator.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims

1. A semiconductor wafer surface based test apparatus, comprising:

a test table for placing a semiconductor wafer;

the bracket is arranged on one side of the test board;

a probe assembly for contacting an upper surface of a semiconductor wafer;

the driving part drives the probe assembly to move downwards by means of the flexible connecting piece to be in contact with the semiconductor wafer, and the probe assembly rotates around the contact end of the probe assembly and the semiconductor wafer by means of the self gravity of the probe assembly until the lower surface of the probe assembly is completely attached to the upper surface of the semiconductor wafer.

2. The semiconductor wafer surface based testing apparatus of claim 1 wherein the flexible connection is a string.

3. The semiconductor wafer surface based test apparatus as recited in claim 1, wherein the bottom end of the flexible connector is provided with three connections to the probe assembly, the connections being evenly distributed along the center of gravity of the probe assembly.

4. The semiconductor wafer surface based test apparatus of claim 1, wherein the probe assembly comprises:

a probe base;

the mercury probe is fixedly arranged on the probe base; and

5. The semiconductor wafer surface based test apparatus as recited in claim 4, wherein the probe base has a recess formed at a top portion thereof, and a pin for fixedly connecting the flexible connection member is formed inside the recess.

6. The semiconductor wafer surface based test apparatus of claim 4, wherein the number of the support bars is two, symmetrically disposed on both sides of the mercury probe tip.

7. The semiconductor wafer surface based test apparatus of claim 4, wherein the support bar is connected to the probe base by a screw thread and has a degree of freedom of rotation about its axis.

8. The semiconductor wafer surface based test apparatus of claim 1, wherein the driving part comprises:

the rotating shaft is rotatably arranged on the bracket;

9. The semiconductor wafer surface based test apparatus as claimed in claim 8, wherein a guide wheel is provided on the support, the guide wheel is located between the driving part and the probe assembly, a guide groove is provided on an outer circumference of the guide wheel, and the flexible connecting member is pressed against a side wall of the guide groove.

10. The semiconductor wafer surface based test apparatus of claim 8, wherein the driving section further comprises:

and the handle is hinged on the end surface of the rotating disc.